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Space Infrared Telescope for Cosmology and Astrophysics (SPICA), the cryogenic infrared space telescope recently pre-selected for a ‘Phase A’ concept study as one of the three remaining candidates for European Space Agency (ESA's) fifth medium class (M5) mission, is foreseen to include a far-infrared polarimetric imager [SPICA-POL, now called B-fields with BOlometers and Polarizers (B-BOP)], which would offer a unique opportunity to resolve major issues in our understanding of the nearby, cold magnetised Universe. This paper presents an overview of the main science drivers for B-BOP, including high dynamic range polarimetric imaging of the cold interstellar medium (ISM) in both our Milky Way and nearby galaxies. Thanks to a cooled telescope, B-BOP will deliver wide-field 100–350
m images of linearly polarised dust emission in Stokes Q and U with a resolution, signal-to-noise ratio, and both intensity and spatial dynamic ranges comparable to those achieved by Herschel images of the cold ISM in total intensity (Stokes I). The B-BOP 200
m images will also have a factor
30 higher resolution than Planck polarisation data. This will make B-BOP a unique tool for characterising the statistical properties of the magnetised ISM and probing the role of magnetic fields in the formation and evolution of the interstellar web of dusty molecular filaments giving birth to most stars in our Galaxy. B-BOP will also be a powerful instrument for studying the magnetism of nearby galaxies and testing Galactic dynamo models, constraining the physics of dust grain alignment, informing the problem of the interaction of cosmic rays with molecular clouds, tracing magnetic fields in the inner layers of protoplanetary disks, and monitoring accretion bursts in embedded protostars.
Determining infectious cross-transmission events in healthcare settings involves manual surveillance of case clusters by infection control personnel, followed by strain typing of clinical/environmental isolates suspected in said clusters. Recent advances in genomic sequencing and cloud computing now allow for the rapid molecular typing of infecting isolates.
To facilitate rapid recognition of transmission clusters, we aimed to assess infection control surveillance using whole-genome sequencing (WGS) of microbial pathogens to identify cross-transmission events for epidemiologic review.
Clinical isolates of Staphylococcus aureus, Enterococcus faecium, Pseudomonas aeruginosa, and Klebsiella pneumoniae were obtained prospectively at an academic medical center, from September 1, 2016, to September 30, 2017. Isolate genomes were sequenced, followed by single-nucleotide variant analysis; a cloud-computing platform was used for whole-genome sequence analysis and cluster identification.
Most strains of the 4 studied pathogens were unrelated, and 34 potential transmission clusters were present. The characteristics of the potential clusters were complex and likely not identifiable by traditional surveillance alone. Notably, only 1 cluster had been suspected by routine manual surveillance.
Our work supports the assertion that integration of genomic and clinical epidemiologic data can augment infection control surveillance for both the identification of cross-transmission events and the inclusion of missed and exclusion of misidentified outbreaks (ie, false alarms). The integration of clinical data is essential to prioritize suspect clusters for investigation, and for existing infections, a timely review of both the clinical and WGS results can hold promise to reduce HAIs. A richer understanding of cross-transmission events within healthcare settings will require the expansion of current surveillance approaches.
Salmonella enterica serovar Wangata (S. Wangata) is an important cause of endemic salmonellosis in Australia, with human infections occurring from undefined sources. This investigation sought to examine possible environmental and zoonotic sources for human infections with S. Wangata in north-eastern New South Wales (NSW), Australia. The investigation adopted a One Health approach and was comprised of three complimentary components: a case–control study examining human risk factors; environmental and animal sampling; and genomic analysis of human, animal and environmental isolates. Forty-eight human S. Wangata cases were interviewed during a 6-month period from November 2016 to April 2017, together with 55 Salmonella Typhimurium (S. Typhimurium) controls and 130 neighbourhood controls. Indirect contact with bats/flying foxes (S. Typhimurium controls (adjusted odds ratio (aOR) 2.63, 95% confidence interval (CI) 1.06–6.48)) (neighbourhood controls (aOR 8.33, 95% CI 2.58–26.83)), wild frogs (aOR 3.65, 95% CI 1.32–10.07) and wild birds (aOR 6.93, 95% CI 2.29–21.00) were statistically associated with illness in multivariable analyses. S. Wangata was detected in dog faeces, wildlife scats and a compost specimen collected from the outdoor environments of cases’ residences. In addition, S. Wangata was detected in the faeces of wild birds and sea turtles in the investigation area. Genomic analysis revealed that S. Wangata isolates were relatively clonal. Our findings suggest that S. Wangata is present in the environment and may have a reservoir in wildlife populations in north-eastern NSW. Further investigation is required to better understand the occurrence of Salmonella in wildlife groups and to identify possible transmission pathways for human infections.
Neck dissection is associated with post-operative shoulder dysfunction in a substantial number of patients, affecting quality of life and return to work. There is no current UK national practice regarding physiotherapy after neck dissection.
Nine regional centres were surveyed to determine their standard physiotherapy practice pre- and post-neck dissection, and to determine pre-emptive physiotherapy for any patients.
Eighty-nine per cent of centres never arranged any pre-emptive physiotherapy for any patients. Thirty-three per cent of centres offered routine in-patient physiotherapy after surgery. No centres offered out-patient physiotherapy for all patients regardless of symptoms. Seventy-eight per cent offered physiotherapy for patients with any symptoms, with 11 per cent offering physiotherapy for those with severe dysfunction only. Eleven per cent of centres never offered physiotherapy for any dysfunction.
The provision of physiotherapy is most commonly reactive rather than proactive, and usually driven by patient request. There is little evidence of pre-arranged physiotherapy for patients to treat or prevent shoulder dysfunction in the UK.
To characterize meal patterns across ten European countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) calibration study.
Cross-sectional study utilizing dietary data collected through a standardized 24 h diet recall during 1995–2000. Eleven predefined intake occasions across a 24 h period were assessed during the interview. In the present descriptive report, meal patterns were analysed in terms of daily number of intake occasions, the proportion reporting each intake occasion and the energy contributions from each intake occasion.
Twenty-seven centres across ten European countries.
Women (64 %) and men (36 %) aged 35–74 years (n 36 020).
Pronounced differences in meal patterns emerged both across centres within the same country and across different countries, with a trend for fewer intake occasions per day in Mediterranean countries compared with central and northern Europe. Differences were also found for daily energy intake provided by lunch, with 38–43 % for women and 41–45 % for men within Mediterranean countries compared with 16–27 % for women and 20–26 % for men in central and northern European countries. Likewise, a south–north gradient was found for daily energy intake from snacks, with 13–20 % (women) and 10–17 % (men) in Mediterranean countries compared with 24–34 % (women) and 23–35 % (men) in central/northern Europe.
We found distinct differences in meal patterns with marked diversity for intake frequency and lunch and snack consumption between Mediterranean and central/northern European countries. Monitoring of meal patterns across various cultures and populations could provide critical context to the research efforts to characterize relationships between dietary intake and health.
The discovery of the fully developed Formative sites of Cotocallao (ca. 3750-2350 cal. B.P.) in the Quito Basin and La Chimba (ca. 2650-1700 cal. B.P.) in the northern highlands of Ecuador has raised questions about their cultural antecedents, which have not been resolved despite decades of archaeological work in the region. Paleoenvironmental coring investigations were conducted at Lake San Pablo in northern highland Ecuador to determine the date for the onset of prehistoric maize farming in the temperate highland valleys of this region. The investigations included analysis of lake sediments for pollen, phytoliths, diatoms, and tephra. Maize pollen was identified as early as 4900 cal. B.P., while maize phytoliths dated even earlier, to 6200 or 6600 cal. B.P. These results demonstrate a long history of maize farming in valleys around Lake San Pablo, but in the context of a punctuated record of major and minor volcanic eruptions. It is concluded that early horticultural sites predating Cotocallao and La Chimba must exist, but to find such sites, archaeologists will have to locate and study deeply buried A-horizon soils.
Disease prioritization is motivated by the need to ensure that limited resources are targeted at the most important problems to achieve the greatest benefit in improving and maintaining human and animal health. Studies have prioritized a range of disease types, for example, zoonotic and foodborne diseases, using a range of criteria that describe potential disease impacts. This review describes the progression of disease prioritization methodology from ad hoc techniques to decision science methods (including multi-criteria decision analysis, conjoint analysis and probabilistic inversion), and describes how these methods aid defensible resource allocation. We discuss decision science in the context of disease prioritization to then review the development of disease prioritization studies. Structuring the prioritization and assessing decision-makers' preferences through value trade-offs between criteria within the decision context are identified as key factors that ensure transparency and reproducibility. Future directions for disease prioritization include the development of validation techniques, guidelines for model selection and neuroeconomics to gain a deeper understanding of decision-making.
Diarrhoeal diseases are major causes of morbidity and mortality in developing countries. This longitudinal study aimed to identify controllable environmental drivers of intestinal infections amidst a highly contaminated drinking water supply in urban slums and villages of Vellore, Tamil Nadu in southern India. Three hundred households with children (<5 years) residing in two semi-urban slums and three villages were visited weekly for 12–18 months to monitor gastrointestinal morbidity. Households were surveyed at baseline to obtain information on environmental and behavioural factors relevant to diarrhoea. There were 258 diarrhoeal episodes during the follow-up period, resulting in an overall incidence rate of 0·12 episodes/person-year. Incidence and longitudinal prevalence rates of diarrhoea were twofold higher in the slums compared to rural communities (P < 0·0002). Regardless of study site, diarrhoeal incidence was highest in infants (<1 year) at 1·07 episodes/person-year, and decreased gradually with increasing age. Increasing diarrhoeal rates were associated with presence of children (<5 years), domesticated animals and low socioeconomic status. In rural communities, open-field defecation was associated with diarrhoea in young children. This study demonstrates the contribution of site-specific environmental and behavioural factors in influencing endemic rates of urban and rural diarrhoea in a region with highly contaminated drinking water.
Emerging and re-emerging infectious disease (EID) events can have devastating human, animal and environmental health impacts. The emergence of EIDs has been associated with interconnected economic, social and environmental changes. Understanding these changes is crucial for EID preparedness and subsequent prevention and control of EID events. The aim of this review is to describe tools currently available for identification, prioritization and investigation of EIDs impacting human and animal health, and how these might be integrated into a systematic approach for directing EID preparedness. Environmental scanning, foresight programmes, horizon scanning and surveillance are used to collect and assess information for rapidly responding to EIDs and to anticipate drivers of emergence for mitigating future EID impacts. Prioritization of EIDs − using transparent and repeatable methods − based on disease impacts and the importance of those impacts to decision-makers can then be used for more efficient resource allocation for prevention and control. Risk assessment and simulation modelling methods assess the likelihood of EIDs occurring, define impact and identify mitigation strategies. Each of these tools has a role to play individually; however, we propose integration of these tools into a framework that enhances the development of tactical and strategic plans for emerging risk preparedness.
Two broad aims drive weed science research: improved management and improved understanding of weed biology and ecology. In recent years, agricultural weed research addressing these two aims has effectively split into separate subdisciplines despite repeated calls for greater integration. Although some excellent work is being done, agricultural weed research has developed a very high level of repetitiveness, a preponderance of purely descriptive studies, and has failed to clearly articulate novel hypotheses linked to established bodies of ecological and evolutionary theory. In contrast, invasive plant research attracts a diverse cadre of nonweed scientists using invasions to explore broader and more integrated biological questions grounded in theory. We propose that although studies focused on weed management remain vitally important, agricultural weed research would benefit from deeper theoretical justification, a broader vision, and increased collaboration across diverse disciplines. To initiate change in this direction, we call for more emphasis on interdisciplinary training for weed scientists, and for focused workshops and working groups to develop specific areas of research and promote interactions among weed scientists and with the wider scientific community.
High blood pressure (BP) variability, which may be an important determinant of hypertensive end-organ damage, is emerging as an important predictor of cardiovascular health. Dietary antioxidants can influence BP, but their effects on variability are yet to be investigated. The aim of the present study was to assess the effects of vitamin E, vitamin C and polyphenols on the rate of daytime and night-time ambulatory BP variation. To assess these effects, two randomised, double-blind, placebo-controlled trials were performed. In the first trial (vitamin E), fifty-eight individuals with type 2 diabetes were given 500 mg/d of RRR-α-tocopherol, 500 mg/d of mixed tocopherols or placebo for 6 weeks. In the second trial (vitamin C–polyphenols), sixty-nine treated hypertensive individuals were given 500 mg/d of vitamin C, 1000 mg/d of grape-seed polyphenols, both vitamin C and polyphenols, or neither (placebo) for 6 weeks. At baseline and at the end of the 6-week intervention, 24 h ambulatory BP and rate of measurement-to-measurement BP variation were assessed. Compared with placebo, treatment with α-tocopherol, mixed tocopherols, vitamin C and polyphenols did not significantly alter the rate of daytime or night-time systolic BP, diastolic BP or pulse pressure variation (P>0·05). Treatment with the vitamin C and polyphenol combination resulted in higher BP variation: the rate of night-time systolic BP variation (P= 0·022) and pulse pressure variation (P= 0·0036) were higher and the rate of daytime systolic BP variation was higher (P= 0·056). Vitamin E, vitamin C or grape-seed polyphenols did not significantly alter the rate of BP variation. However, the increase in the rate of BP variation suggests that the combination of high doses of vitamin C and polyphenols could be detrimental to treated hypertensive individuals.
Due to an increased need for new antimalarial chemotherapies that show potency against Plasmodium falciparum, researchers are targeting new processes within the parasite in an effort to circumvent or delay the onset of drug resistance. One such promising area for antimalarial drug development has been the parasite mitochondrial electron transport chain (ETC). Efforts have been focused on targeting key processes along the parasite ETC specifically the dihydroorotate dehydrogenase (DHOD) enzyme, the cytochrome bc1 enzyme and the NADH type II oxidoreductase (PfNDH2) pathway. This review summarizes the most recent efforts in antimalarial drug development reported in the literature and describes the evolution of these compounds.
Adenoidectomy is often carried out in children for conditions such as nasal obstruction, otitis media with effusion, and obstructive sleep apnoea. Traditionally, it is performed as a blind procedure with a St Clair Thomson curette. An acceptable alternative technique is suction diathermy adenoidectomy. This study aimed to ensure that the complication rate of this latter technique was within published rates and national guidelines.
A retrospective case note review was conducted, and information regarding surgery, indications and complications was collected.
Post-operative haemorrhage was recorded for 2 of 121 patients (at days 10 and 11 post-operatively): 1 returned to the operating theatre and the other was managed conservatively. Two patients were diagnosed with infection post-operatively and managed with oral antibiotics. A further four patients re-presented with pain; in all cases, this was recorded as secondary to tonsillar fossa infection, rather than being pain related to adenoidectomy.
Given the rare but serious potential complications, the authors support National Institute for Health and Clinical Excellence guidance, which recommends that only surgeons with specific training perform this technique. By using the standard procedures for clinical governance, it is possible to ensure safe practice of even little-used techniques.
The slow dynamics and linearized stability of a two-spike quasi-equilibrium solution to a
general class of reaction-diffusion (RD) system with and without sub-diffusion is
analyzed. For both the case of regular and sub-diffusion, the method of matched asymptotic
expansions is used to derive an ODE characterizing the spike locations in the absence of
any 𝒪(1) time-scale instabilities of the two-spike quasi-equilibrium profile. These fast
instabilities result from unstable eigenvalues of a certain nonlocal eigenvalue problem
(NLEP) that is derived by linearizing the RD system around the two-spike quasi-equilibrium
solution. For a particular sub-class of the reaction kinetics, it is shown that the
discrete spectrum of this NLEP is determined by the roots of some simple transcendental
equations. From a rigorous analysis of these transcendental equations, explicit sufficient
conditions are given to predict the occurrence of either Hopf bifurcations or competition
instabilities of the two-spike quasi-equilibrium solution. The theory is illustrated for
several specific choices of the reaction kinetics.
The stability of a one-spike solution to a general class of reaction-diffusion (RD)
system with both regular and anomalous diffusion is analyzed. The method of matched
asymptotic expansions is used to construct a one-spike equilibrium solution and to derive
a nonlocal eigenvalue problem (NLEP) that determines the stability of this solution on an O(1) time-scale. For a particular sub-class of the reaction
kinetics, it is shown that the discrete spectrum of this NLEP is determined in terms of
the roots of certain simple transcendental equations that involve two key parameters
related to the choice of the nonlinear kinetics. From a rigorous analysis of these
transcendental equations by using a winding number approach and explicit calculations,
sufficient conditions are given to predict the occurrence of Hopf bifurcations of the
one-spike solution. Our analysis determines explicitly the number of possible Hopf
bifurcation points as well as providing analytical formulae for them. The analysis is
implemented for the shadow limit of the RD system defined on a finite domain and for a
one-spike solution of the RD system on the infinite line. The theory is illustrated for
two specific RD systems. Finally, in parameter ranges for which the Hopf bifurcation is
unique, it is shown that the effect of sub-diffusion is to delay the onset of the Hopf
This trial aimed to compare the guillotine technique of tonsillectomy with ‘cold steel’ dissection, the current ‘gold standard’.
A single centre, randomised, controlled trial.
One hundred children aged 3 to 11 years who were listed for bilateral tonsillectomy were recruited. Patients had one tonsil removed by each technique, and were blinded to the side. The operative time, intra-operative blood loss, haemostasis requirement and post-operative pain scores were recorded and compared.
Operative time and intra-operative blood loss were both significantly less for the guillotine technique (p < 0.001) and there was a significantly reduced haemostasis requirement (p < 0.001). Pain was also less on the guillotine side (p < 0.001). There were no tonsillar remnants or palatal trauma for either technique. There was no significant difference between techniques in the frequency of secondary haemorrhage.
This study provides level Ib evidence that guillotine tonsillectomy in children with mobile tonsils is an effective and time-efficient procedure which produces less intra-operative blood loss and post-operative pain than cold steel dissection.
Highly localized metal deposits can be produced at low temperature by direct writing using a focused laser beam to induce photodissociation of gaseous organometallic precursors. The deposition rate and localization of the deposit are influenced by the kinetics of photochemical reaction and transport of reactants and products. Two-dimensional finite-element computations were performed to determine the effect of deposition parameters, such as laser power, precursor concentration, system pressure, and sticking coefficient, on deposition rates and deposit profiles resulting from single-photon gas-phase dissociation of organometallic precursors. The effect of various gas-phase transport regimes and the conditions and importance of reactant depletion have been investigated. Numerical results have also been compared to theoretical and experimental results from the literature.
Discontinuously reinforced aluminum (DRA) composites with enhanced fracture toughness have recently been developed at ALCOA. The approach consists of producing a composite microstructure in which discrete ductile phases have been incorporated into the DRA through traditional powder processing routes. In the present paper, the high strain rate behavior of these toughened composites is investigated by obtaining (i) the dynamic flow characteristics at various levels of elevated strain rates using a split Hopkinson compression bar, and (ii) energy absorption during dynamic crack initiation and crack propagation using three-point bend specimens loaded on a modified Hopkinson bar configuration.
Evaporation induced self assembly (EISA) within microdroplets produced by a vibrating orifice aerosol generator (VOAG) has been used to produce monodisperse mesoporous silica particles. This process exploits the concentration of evaporating droplets to induce the organization of various amphiphilic molecules, effectively partitioning the silica precursor (TEOS) to the hydrophilic regions of the structure. Promotion of silica condensation, followed by removal of the surfactant, provides ordered spherical mesoporous particles. Using the VOAG we have produced highly monodisperse particles in the 5 to 10 μm diameter range. The cationic surfactant CTAB typically leads to hexagonal mesostructure with mean pore size of about 2 nm and specific surface area around 900 m2/g. We have also shown that the pore size in CTABtemplated particles can be increased to 3.8 nm by incorporating trimethylbenzene as a swelling agent. The TMB prefentially locates inside and swells the hydrophobic regions of the surfactant mesostructure. Pore size can also be varied by the choice of amphiphile. Hexagonally ordered particles have been produced using the nonionic surfactant Brij-58 and block copolymer F127. These powders possessed mean pore size 2.8 nm and 6.9 nm, respectively. The uptake of alkyl pyridinium chloride molecules have recently been measured, revealing an uptake capacity that is explained by surface adsorption (as opposed to simple pore infiltration). Kinetics of the uptake process are still be analyzed.